Method and apparatus for the circular knitting of hook and loop fastener elements

ABSTRACT

In combination with a circular knitting machine means are disclosed for knitting upstanding loops attached to a base fabric to produce a looped pile and means incorporating the use of an ultrasonic transducer for converting loops into hooks and for thermosetting the loops.

United States Patent 191 Conroux et al.

[ Oct. 16, 1973 METHOD AND APPARATUS FOR THE CIRCULAR KNITTING OF HOOK AND LOOP FASTENER ELEMENTS [75] Inventors: Jean-Jacques Conroux; Christian Pierre Jonville; Erwin Alair Ziircher, all of Geneve; Daniel Henri Philippe Pilet, Founex, all of Switzerland; Claude Henri Guignard, Ferney-Voltaire, France [73] Assignee: Societe Pour La Recherche et Le Developpelnent Technologiques (usoretn) [22] Filed: June 12, 1970 [21] Appl. No.: 45,664

[56] References Cited UNlTED STATES PATENTS 3,673,301 6/1972 Billarant 26/9 X 3,674,602 7/1972 Keogh et al.... 156/73 X 2,717,437 9/1955 Mestral 28/72 P X Manock 156/73 3,640,786 2/1972 Carpenter 156/73 3,654,054 4/1972 Waller 66/194 537,748 4/1895 Brown 66/91 3,241,337 3/1966 Stevens, .lr... 66/9 R X 3,015,223 l/1962 Moore 66/147 3,083,737 4/1963 Mestral 26/9 X 3,576,690 4/1971 Strats et al.... 156/73 3,586,555 6/1971 Sager 156/73 3,530,687 9/1970 l-lamano.... 66/147 X 3,539,436 11/1970 Hamano.... 66/192 UX I 3,586,060 6/1971 Erb 26/9 X 3,331,220 7/1967 Bastuscheck et a1. 66/140 R X 2,933,908 4/1960 Thore 66/147 2,485,230 10/1949 Alexander et a1 66/147 UX FOREIGN PATENTS OR APPLICATIONS 1,539,997 8/1968 France 66/86 R Primary Examiner-Wm. Carter Reynolds Att0rneyPennie, Edmonds, Morton, Taylor and Adams [57] ABSTRACT In combination with a circular knitting machine means are disclosed for knitting upstanding loops attached to a base fabric to produce a looped pile and means incorporating the use of an ultrasonic transducer for converting loops into hooks and for thermosetting the loops.

8 Claims, 11 Drawing Figures PATENTEDUCI 1 s 1975 SHEET 10F 5 FIG. 1;,

INVENTORS JEAN JACQUES CONROUX CHRISTIAN F. JONVILLE ERWIN A. ZURCHER DANIEL H. P. PiLET CLAUDE H. GUIGNARD ATTORNEYS PAIENIEDBBHBW 3,765.193

' .SHEEI 2 or 5 INVENTORS J'E JACQUES CONROUX CH TIAN I? J'ONVILLE RCHER ERWIN A.: ZU

'DANIELHL P. Pl

CLAUDE H. GUI RD %M,%%

AT TO RN EYS PAIENIED DU 1 61973 FIG. 40

FIG. 4

SHEET 3 BF 5 INVENTORS J'EAN CQUES CONROUX CHRIS N F. J'ONVILLE ERWIN A. ZURCHER DANIEL H. P. PILET CLAUDE H. GUIGNARD BY %0'% W ;;flQ/%w ATTORNEYS Pmmnnnm 3.765.193

SHEEI 0F 5 INVENTORS CHRISTIAN P. J'ONVILLE ERWIN A. ZURCHER DANIEL H. P. PILET CLAUDE H. GUIGNARD ATTO RNEYS SHEEI 5 BF 5 INVENTORS J'EAN :rAcQuEs CONROUX CHRISTIAN P. JONVILLE ERWIN A. ZURCHER DANIEL H. P. PILET ,;'CLAUDE H. GUIGNARD /gwzamww. 4%,; 4m ATTORNEYS mm mm PATENIED U 1 75 BACKGROUND OF THE INVENTION Hook and loop fasteners are well known and have generally been produced by weaving techniques using special apparatus and methods necessary to affect the production of interconnecting hook and loop fastener elements. Such fasteners have found many applications and operate by having a miltiplicity of hooks of one fastener element interengage with loops in a complementary fastener element. Separation is normally obtained by peeling the respective fastener elements one from the other.

.Proposals have been advanced to produce hook and loop fasteners using knitting techniques since looped stitches are naturally formed during knitting. Warp knitting is known which utilizes stationary lancettes upon which loops are formed.

The present invention contemplates novel means for knitting a looped pile fabricusing circular knitting techniques. Because of the construction and design of circular knitting machines generally, a serious problem is thus presented when pile forming lancettes are to be employed since how to fix such lancettes relative to the rotary portions of the machinery is not readily done.

A further problem for which the present invention provides a solution involves the cutting of pile loops in order to form hooks when it is desired to produce the hooked fastener portion of a hookand loop fastener. The means provided may be readily usedin conjunction with circular knitting apparatus or in conjunction with other pile knitting or pile weaving apparatus.

SUMMARY OF THE INVENTION In accordance with the invention, a modified circular knitting machine is provided having reciprocating needles and yarn bobbins which rotate circumferentially relative to these needles. Adjacent to one or more needles is located a lancette and various embodiments of the invention provide means for holding the lancettes in position. One such means comprises a bearing mounted support interconnecting the lancette and the bobbin rotating portions of the machine. Such support fixes each lancette, relative to each other and prior to the knitting operation fixes the lancettes relative to the needles. However, a major support for the lancettes will also be the interengagement of each lancette with the fabric as it is knitted.

As a further aspect of the present invention, ultrasonic transducer means are provided in conjunction with the aforementioned lancettes to produce when de-- sired a hooked pile suitable for interengagement with the looped pile otherwise produced by a circular knitting apparatus. In accordance with this aspect, as the loops pass over the lancettes immediately after being formed thereupon, one upstanding leg of each loop is cut by ultrasonic knife means and simultaneously, the loops are subjected to ultrasonic vibration in order to thermally set the loops. The material forming the loop and base fabric will be of nylon, polyester or other thermally setting yarns.

These and other aspects of the invention will be readily seen from an examination of the description of a preferred embodiment which follows and of the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a vertical cross-section of portions of a circular knitting machine, loop forming apparatus and ultrasonic transducer cutting and setting means;

FIG. 2 is a fragmentary, enlarged cross-section of portions of the loop forming lancette of FIG. land of base portions of the transducer of FIG. 1;

FIG. 3 is a section taken in the direction of arrows 33 of FIG. 2.

FIGS. 4a-4f illustrate the knitting sequence of the knitting machine shown in FIG. 1; and

FIGS. 5 and 6 illustrate knitting machine embodiments incorporating different lancette securing means.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawing and initially to FIG. 1 thereof, portions ofa circular knitting machine 10 have been illustrated. The machine 10 comprises a frame 11 which journals a drive shaft 12 connected to a driving pinion 13. The pinion 13 drives a circular cogwheel 14 which mounts a bobbin shaft 16. Bobbins l7 and 18 are secured to the shaft 16 upon plate 19. The cogwheel 14 rotates in a horizontal plane, the shaft 16 and bobbins 17, 18 are carried about the circumference of the inner frame structure 11b.

Held within and reciprocably movable with respect to the inner frame 11b are a plurality of latch type needles 20. The needles 20 are caused to reciprocate by means of cams 21 within cam support 21b as cogwheel 14 moves around inner frame element 11b. Yarns 22 and 23 are fed respectively about yarn guides 24, 25 and 26 from bobbins 17 and 18 to yarn guides 25a and 26a respectively. The yarn 22 forms the base fabric while the yarn 23 forms loops as will be seen.

The bobbin shaft 16 mounts a circular member 27 having a series of ball bearings 28. In bearing engagement therewith is another circular element 30 whose purpose is to provide support for a plurality of lancettes 31 secured thereto. In accordance with the invention, the lancettes 31 cooperate with the knitting cycle of individual needles 20 and with the movement of the yarns 22 and 23 to effect the knitting of a base fabric 32 and a series of loops 33 formed about the lancette 31. It will be seen that as the loops are formed, they engage about the lancette 31 providing additional support for the lancette whose main support is the bearing 28.

It will be understood that a lancette may be provided for each pair of needles but that there are other possible needle and lancette combinations, a lancette being used with one or several needles to form loops integral with a base fabric.

FIGS. 4a-4f illustrate the formation of base fabric and loops using the apparatus of FIG. 1. In FIG. 4a, the needle is at its starting position having just risen and during the course of such motion the latch 20a will be opened by the last stitch. In FIG. 4b, the needle has completed its rise and the stitches have fallen from the latch 20a to a stem 20b of the needle. In FIG. 40 the needle has begun to descend and new yarns 23, 22 are introduced above and below the lancette 31 by the rotating bobbins. In FIG. 4d, the needle continues to descend, both yarns are taken from the needle and the preceding stitch has closed the latch 20a. In FIG. 4e the needle continues to descend and both new loops comprising yarns 23, 22 have formed stitches by passing through the preceding stitches. The upper yarn 23 forms a loop 33 by passing around the lancette 31. In FIG. 4f the needle has completed its descent and the new stitch is pulled through to its full length.

Thus far has been described the production ofa knitted base fabric and upstanding loops therefrom using the modified circular knitting apparatus of the invention. In the case where a looped pile is to be knitted to be used as the looped portion of a hook and loop fastener, the yarn 23 will comprise a multifilament nylon and after the loops have been formed about the lancette 31, further treatment'may consist ofa brushing or napping step to provide maximum disorientation and to facilitate engagement of hooks therein.

The present invention further provides for cutting the loops 33 when formed of a monofilament such as ny- Ion, polyester and other thermosetting yarns. This is accomplished through the agency of an ultrasonic transducer 34 whose operation will now be described. The ultrasonic transducer 34 will be mounted by any convenient means in the position shown in FIG. 1. The transducer may be a unitary ring shaped transducer as shown in the drawings, or it may be a transducer formed to have a ring-like configuration by placing a series of transducers end to end. As will be seen with respect to FIGS. 2 and 3, the base 34a of the transducer is formed as a series of extensions 340 which surround lancettes 31 on both sides thereof. Loops 33 will be pressed into contact with upper sides of lancettes 31 by extensions 34c and will bow out of contact somewhat with the sides of the lancettes. Knives 36 are bolted to the transducer 34, the ends 3611 of which extend slightly within a recess 31a of each lancette. As the loops 33 pass overa lancette 31, one side 3311 of each loop is cut by a knife end 36a which will leave a small space or gap 33b where the knife edge passes through the portion of the loop. By this means a series of hooks 38 will be formed. Simultaneously, the close proximity of the lancette 31 to the ends 34c of the transducer 34 and to the knife ends 36 cause the lancettes 31 to heat set the monofilament material of the loops 33 and hooks 38. Thus the hooks 38 though still flexible will become quite resilient and able to perform their function without permanent deformation. Due to the Proximity of the material ofthe base fabric layer 32 to the loops and the lancettes 31, some heat will be transferred to the base fabric.

Referring to the embodiments illustrated in FIGS. and 6, there have been shown schematically alternate arrangements of knitting apparatus including particular means for fixing the pile forming lancettes relative to the frame 61. With reference initially to FIG. 5, the pile yarn bobbins 40 and base fabric bobbins 41 are interconnected by suitable gearing 43, 44 with a drive shaft 45. The latter is driven by pinion 46 interconnecting with pinion 47 powered by suitable drive means. The bobbins 40 and 41 are mounted on cogwheels 48, 49 supported by plates 50, 51. The latter are attached to a shaft 52 and are in bearing engagement with the cogwheels 48, 49 so as to permit relative rotation of these and the bobbins 40, 41 about the shaft 52.

A plurality of L-shaped lancettes 54 are attached at their upper ends 54a with a rigid cylindrical housing 56. The housing and thus the lancettes 54 are rigidly attached by a collar 57 to the hollow shaft 52. Needles 58 are opositioned each adjacent to a lancette 54 and vertically reciprocate relative thereto. A camming and cam actuating means 59 causes reciprocation of the needles. The needles 58 are held during the vertical movement within a stationary ring 60 which is rigidly secured to base 61. Ring 60 is connected to the shaft 52 to impart fixed rigidity thereto.

The apparatus of FIG. 6 also illustrates an alternate arrangement whereby loop pile fabric may be produced in accordance with circular knitting techniques. In the apparatus of FIG. 6, a central stationary platform 65 is secured to a shaft 66 which journals a drive shaft 67. The input power to the shaft 67 is indicated by reference numeral 68. Attached to shaft 67 and rotatable therewith are a plurality of base and loop yarn bobbins 69 and 70. Lancettes 71 are rigidly secured at their ends 71a to a housing 72 which is secured to the shaft 66 at 73.

The support for bobbin 69 is a housing 74 which further mounts needle actuating cam 75. Needles 76 are horizontally disposed and reciprocable with respect to platform 65 upon rotating movement of cam 75.

In accordance with the above-described embodiments of circular knitting apparatus, it will be seen that means in the form of lancettes are embodied to provide the formation of a looped pile and base fabric. In each case there is relative movement between the lancettes and bobbins supplying loop and base fabric yarn. In the particular embodiments illustrated the lancettes are stationary while the bobbins rotate relative thereto; however, the invention contemplates the possibility that the lancettes may be movable and the bobbins stationary. In any case, a particular feature of the invention is the discovery that the lancettes will be held firmly in place once the knitting process has begun by engagement with the looped pile. This engagement for example prevents (in the embodiment of FIG. 1) rotating movement of the lancettes 31 which might tend to occur due to the frictional forces within bearing element 27. It is the discovery that the lancettes will be held quite securely by the fabric which permits the relatively simple design adaptation of FIG. 1.

The invention is further directed in a separate broad aspect to the processing of looped pile fabric to convert same into hooked pile. The means and method employed are the use of ultrasonic vibrations simultaneously to set the yarn thermally and to cut loops to form hooks.

The above description relates to particular embodiments of the invention and is therefore representative. In order to appreciate the scope ofthe invention reference should be made to the appended claims.

What is claimed is:

1. Apparatus for setting and cutting loops of a thermoplastic material upstanding from a base fabric of the same material comprising a lancette, means for passing said loops in a series over said lancette, transducer means surrounding said lancette in close juxtaposition thereto, knife means connected to said transducer means, said knife means being positioned to contact an upstanding leg portion of each loop as said loop passes over the lancette thereby causing said upstanding leg to be cut and said loop to be converted into a hook, said transducer means also simmultaneously causing said loops to be thermoset.

2. The apparatus of claim 1 wherein said transducer means surrounds several lancettes and is placed close to said base fabric.

3. The apparatus of claim 1 in combination with circular knitting apparatus for creating said base fabric and loops.

4. A method of cutting and heat setting a series of upstanding loops to form a hooked fastener element comprising passing said loops in a row over a lancette, and subjecting one upstanding leg of each loop to the cutting action of (a) an ultrasonic transducer element while simultaneously causing said transducer element (to agitate said lancette at ultrasonic frequencies in order) to set the material of said loops.

5. Amethod according to claim 4 in which loops project from a base fabric of the same material as said loops.

6. A method of producing a fabric having a plurality of hook-like elements upstanding therefrom suitable for use as part of a hook and loop-type fastener comprising knitting by circular knitting techniques a base fabric layer and simultaneously knitting a sequential series of loops upstanding from said base fabric layer about a lancette, setting said loops by an ultrasonic transducer while the loops are around said lancette, and cutting at least some of said loops to form hooks.

7. An apparatus for setting loops of. a thermoplastic material such as nylon upstanding from a base fabric of the same material comprising a lancette, means for passing said loops in a series over said lancette, and ultra-sonic transducer means surrounding said lancette in close relation thereto to cause said loops to be thermoset.

8. The apparatus according to claim 7 wherein said transducer means is placed close to said base fabric as well as said loops.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent 3,765,193 Dated October 16 1973 Jean Jacques Conrous et a1. Inventor(s) It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

In 1, numeral 25a should have a lead line directed to the yarn guide as shown in the attached drawing. I

Column 3, line 67 change opositioned" to positioned Column 6, claim 6, line 4, change "setting" to the rmosetting Column 6, I claim lines 10 and '11, change "ultra-sonic" to w ultrasonic i I I n C C Y a signed and s eal'ed this v.1. 71:h ay September 19 (SEAL) Attest: I

McCOY M.. GIBSON c WSgALL DANN Attesting Officer commlsslon Q atents FORM P0-1050 (IO-69) v YUSCOMWDC I i 15. GOVERNMENT [Ri N TING OFFICE Hi9 0-368-834. .1 

1. Apparatus for setting and cutting loops of a thermoplastic material upstanding from a base fabric of the same material comprising a lancette, means for passing said loops in a series over said lancette, transducer means surrounding said lancette in close juxtaposition thereto, knife means connected to said transducer means, said knife means being positioned to contact an upstanding leg portion of each loop as said loop passes over the lancette thereby causing said upstanding leg to be cut and said loop to be converted into a hook, said transducer means also simmultaneously causing said loops to be thermoset.
 2. The apparatus of claim 1 wherein said transducer means surrounds several lancettes and is placed close to said base fabric.
 3. The apparatus of claim 1 in combination with circular knitting apparatus for creating said base fabric and loops.
 4. A method of cutting and heat setting a series of upstanding loops to form a hooked fastener element comprising passing said loops in a row over a lancette, and subjecting one upstanding leg of each loop to the cutting action of (a) an ultrasonic transducer element while simultaneously causing said transducer element (to agitate said lancette at ultrasonic frequencies in order) to set the material of said loops.
 5. A method according to claim 4 in which loops project from a base fabric of the same material as said loops.
 6. A method of producing a fabric having a plurality of hook-like elements upstanding therefrom suitable for use as part of a hook and loop-type fastener comprising knitting by circular knitting techniques a base fabric layer and simultaneously knitting a sequential series of loops upstanding from said base fabric layer about a lancette, setting said loops by an ultrasonic transducer while the loops are around said lancette, and cutting at least some of said loops to form hooks.
 7. An apparatus for setting loops of a thermoplastic material such as nylon upstanding from a base fabric of the same material comprising a lancette, means for passing said loops in a series over said lancette, and ultra-sonic transducer means surrounding said lancette in close relation thereto to cause said loops to be thermoset.
 8. The apparatus according to claim 7 wherein said transducer means is placed close to said base fabric as well as said loops. 